1. Field of the Invention
The present invention relates to a flameproofing agent for polyamide resins and more particularly to a flameproofing agent that causes no deterioration in the mechanical properties of the polyamide to which it is added.
2. Description of the Prior Art
Flameproofing has been found to be necessary for a variety of resins used for electrical parts, instruments, and interior materials. However, while these materials are effectively flameproofed, their overall safety is not satisfactory as a result of a decrease in mechanical strength. For flameproofing polyamides, certain halogen-containing compounds or mixtures of the halogen-containing compounds with antimony compounds or other Group V metal compounds have been found effective. Although the flameproofing effects on the polyamides by these compounds are relatively high, in order to impart sufficient flameproofing effect, a large amount, such as 20-40 wt%, of the flameproofing agent is required. As a result, the resulting polyamide articles have inferior mechanical properties, especially low impact strength. Moreover, those flameproofing agents are toxic or generate toxic gases when decomposed. Accordingly, the flameproofing agents are not considered safe and the polyamide articles containing large amounts of the flameproofing agent can cause extensive pollution.